1. Field of the Invention
The present invention relates generally to a camera shutter construction and, more particularly, to a camera shutter for carrying out an exposure operation by controlling the opening and closing of shutter sectors.
2. Background Information
In a conventional camera shutter, opening and closing operations of an opening lever and a closing lever for opening and closing sectors of the shutter, respectively, are controlled, inter alia, by electromagnets for carrying out an exposure operation. The opening and closing operations of the opening and closing levers are controlled by changing the timing for turning OFF a current supplied to the electromagnets to thereby carry out the exposure operation. Furthermore, contact pieces for outputting a trigger signal of a stroboscope for emitting light are installed at a position in the vicinity of the opening lever, so that when the opening operation of the opening lever is completed, the contact pieces output the trigger signal and the stroboscope emits light. Likewise, contact pieces for outputting a signal for winding-up film are installed at a position in the vicinity of the closing lever, so that when the closing operation of the closing lever is completed, the contact pieces output the signal to wind-up the film.
In a conventional method of determining whether the operation for opening the shutter sectors has been carried out in the foregoing conventional camera shutter construction, a non-opening state of the shutter sectors is detected when the signal for winding-up the film has been outputted before the current supplied to the electromagnet associated with the opening lever is turned OFF after the shutter is released.
However, in the foregoing conventional shutter structure and operation, even when current supplied to the electromagnet associated with the opening lever is turned OFF, a determination of whether the operation for opening the shutter sectors has been carried out cannot be effectively made and, therefore, a non-opening state of the shutter sectors cannot be effectively detected.
The present invention overcomes many of the disadvantages inherent in conventional camera shutters by providing a camera shutter which is capable of effectively detecting a non-opening state of shutter sectors.